1. Thorax and abdomen blackish, thorax with distinct broad longitudinal stripes.............. .................................................................................................... I. tristis (Bigot) (p. 91)

­ Thorax and abdomen metallic green to blue, thorax without distinct broad stripes..... 2

2. Basicosta yellow............................................................................................................ 3

­ Basicosta black.............................................................................................................. 4

3. Parafacial with pale setulae on lower part, setulae relatively dense and longer than 2–3 x as long as width of 1 st flagellomere (not recorded from Namibia)............................... .................................................................................................... I. dubiosa (Villeneuve)

­ Lower part of parafacial predominantly with black setulae, setulae partly 2–3 x as long as width of 3 rd antennal segment ............................................ I. deserti (Karsch) (p. 91)

4. Katepisternum and anepimeron largely clothed in fuscous to black hairs; facial carina short, distinctly developed between antennae above tip of 1 st flagellomere; hind tibia with 0–1 av; eyes separated by less than width of ocellar triangle in ♂; frons index 0.07 in ♂ ........................................................................................ I. darwini (Curran) (p. 90)

­ Katepisternum and anepimeron largely clothed in yellowish hairs; facial carina long, more or less developed even below tip of 1 st flagellomere; hind tibia with 2–3 av; eyes separated by more than width of ocellar triangle in ♂; frons index 0.12–0.15 in ♂, 0.29 in ♀ .................................................................................... I. hauwangai sp. nov. (p. 91)